The present invention is directed to shaving implements for use in the removal of hair from skin. Accordingly, the term xe2x80x9cimplementxe2x80x9d as used herein should be broadly construed to include one-piece razors and disposable razor cartridges adapted to releasably engage a razor handle.
Historically, developers of razors used for shaving have striven to achieve two seemingly divergent objectives. The first is to provide the user with an implement that will produce the closest shave possible. The second objective is to make the use of the shaving implement as comfortable as possible. The difficulty occurs due to the fact that to achieve a close shave the exposure to the skin of the razor blade, or blades, incorporated into the implement should be maximized. This increases the potential for nicks and cuts in the user""s skin. Where multiple razor blades are incorporated into the shaving implement there is the tendency for the skin to bulge between the blades further increasing the possibility for injury. Therefore to increase the comfort of a shaving operation, the exposure of the razor blades to the user""s skin should be minimized. Attempts to address this dichotomy of objectives have been made in the prior art.
For example, some multi-bladed shaving implements incorporate spacers between the blades, which extend past the shaving plane, thereby reducing the amount of blade exposure to the user""s skin. Alternatively, wires are sometimes wrapped over the blades. While increasing comfort, the closeness of the shave can be adversely affected by the use of spacers or wire.
One method for increasing the closeness of a shave when razors incorporating the above-described spacers have been used is to increase the number of blades in the shaving implement. However, razor blades are typically mounted in shaving implements in fixed relationship relative to one another and tend not to closely follow the contours of the user""s skin. Where multiple razor blades are employed, even pivoting shaving heads tend not to provide sufficient contour following capabilities. Accordingly, while increasing the number of blades improves the closeness of a shave, there is still a need for at least some of the blades to have the ability to follow the contour of a user""s skin.
Based on the foregoing, it is the general object of the present invention to provide shaving implements that overcome the drawbacks and problems associated with prior art showing implements.
The present invention is directed in one aspect to a shaving implement having a shaving head defined in part by an approximately rigid guard and a cap. The approximately rigid guard and the cap being spaced apart from, and approximately parallel to one another. A static blade is secured to the shaving head between the guard and cap and defines a cutting edge approximately parallel thereto. The cutting edge of the static blade is adjacent to a plane, referred to by those skilled in the pertinent art to which the invention pertains as a xe2x80x9cshaving plane.xe2x80x9d The shaving plane is oriented along a line tangent to the guard and cap and extends longitudinally thereof. A cavity is defined by the shaving head adjacent to the static blade, and is adapted to slidably receive a cartridge having at least one dynamic blade mounted therein. The dynamic blade also includes a cutting edge that is approximately parallel to the cutting edge of the static blade when the cartridge is positioned within the cavity. Biasing means are provided for urging the cartridge toward a neutral position in response to forces exerted against the dynamic blade. Once in the neutral position the cutting edge of the dynamic blade extends past the shaving plane. Accordingly, during a shaving operation, the cartridge is slidingly movable within the cavity in response to forces exerted against the dynamic blade, with the biasing means providing a restoring force that moves the cartridge to the neutral position when the forces are removed from the dynamic blade.
In the preferred embodiment of the present invention, the biasing means is in the form of a resilient strip mounted onto posts protruding from the shaving head approximately opposite the cutting edge of the static blade. Preferably, the resilient strip is metallic and made from spring steel, however, the present invention is not limited in this regard as other materials such as resilient polymers or rubbers may be employed. The resilient strip is in communication with the above-described cartridge. During a shaving operation, force exerted by a user from pressing the dynamic blade against skin causes the cartridge to move relative to the shaving head. The resilient strip acts to at least partially counteract this force thereby urging the cartridge toward the neutral position, allowing the dynamic blade to follow the contours of the user""s skin.
Preferably, the shaving implement of the present invention includes two static blades and two dynamic blades. The two static blades define a gap therebetween with a plurality of rails positioned in the gap and spaced apart from one another. The rails each extend along facing surfaces of the static blades approximately perpendicular to the cutting edges. In addition, a second set of rails is positioned on the static blade proximate to the cavity. Similarly, these rails are spaced apart from one another and extend along the blade approximately perpendicular to the cutting edge thereof. Each rail in the second set of rails defines a surface that extends into the cavity that is adapted to slidably support the cartridge.
It is desirable that all of the rails define a tip portion extending past the shaving plane for engaging the skin of a user during a shaving operation. These tip portions are generally rounded and serve to limit the exposure of skin to the blades as the shaving head is drawn across the skin during a shaving operation.